Compressor



P s. w. LUITWIELER 1,775,286

COMPRES 50R filed July 28, 1927 2 ShOOtS-ShBQt 2 Ii finder St ll 114.6 twieler Patented Sept. 9, 1930 PATENT GFFICE SAMUEL W. LUITWIELER, OF LOS ANGELES, CALIFORNIA COMPRESSOR Application filedIuly 28,

My invention is a compressor suitable for compressing gases in connection with refrigcrating machines;

An object of my invention is the construction goif'acompressor for compressing gases andwvapors from refrigerating machines to condense these'into a liquid, and to provide a type of compressor which will operate without vibration and substantially noiselessly. My compressor is particularly adaptedfor use with household refrigerating machines where the :vibration of the compressor isdisagreeable;

Another object of my invention is com- #16 pressor of a double stroke type having a pair o-fpistonsin alignment, these being operated by acam mounted on a power shaft. I j

i In constructing my invention I utilize a frame with a casing in-which is mounted a camfon the power: shaft. A pairof aligned pistons "have a connecting yoke which,-'by means of rollers, is operated ,by the cam. Each of the pistons hasanopening at .the base toallow passage of the gases and has a valve at'its outer end, this valve being spring seated, the valve closing on the compression stroke of the piston and driving the compressed gases out of the dischargepipes into a tarrlgflrthe discharge pipes having check valves.

"Myinvention may be more readily understood from the following description and d-rawings,'in which: 7

Figure 1 is .partialendelevation and par- 1.85 tia'l centralsection.

" Figure 2- isja' half side I elevation partly 7 broken away, andhalf central verticalv section.. L

Tigure; *3 "is v a vertical transverse section 1&0 throngh-one ofthe cylinders and its piston the arrows. I I Figure "4 is a side elevation showing the assembly of compressor with an electric n :1i 33 of F ig. 2 in thedirection of $5 motor.

" able-frame di mounted on aba-se 12, this frame 1927. Serial No. 208,969.

having side walls 13 connected by end walls 14, one of the side walls 13 being provided with a cover plate 15. This forms a chamber 16 to accommodate the cam and the common yoke, as hereunder set forth. Each end of the casing is provided with a flange 17 to each of which is bolted a cylinder 18, the cylinders being provided with heat radiating fins 19. Each of the cylinders is provided with a head 20 bolted thereon, each head having a discharge passage 21 connected to an outlet passage 22, there being a check valve 23 seated in each outlet passage and pressed into position by a spring 24 which bears against a cage 25. The compressed gases are carried by pipes 26 to a common receiving tank 27 which is removably held in the frame 11 by set screws 27. I

The drive shaft 28 is mounted in suitable journals 29 and 30 in the back wall 13 and the cover plate 15, respectively, there being suitable bushings, and a packing '31 and 32 is used on the side of the shaft passing through the back wall, there being a suitable gland nut 33. The other end of the shaft is enclosed by a cover nut .34. The shaft has a pulley 35 thereon which is driven by a belt 36 from the electric motor 37.

The pistons 38 having oil grooves 38 are connected by a common yoke 39, this yoke having a vertical slot 40 therein to accommodat'e the cam, as hereunder mentioned, and horizontal slots 41' on opposite sides to accommodate the drive shaft 28. There is a gas intake 42 into the chamber 16; and a port 43 leads into a chamber 44 in each of the pistons through the base thereof.

Each piston has a plug 45 screw-threaded into its outer end, each of these plugs having passages 46 therethrough and having a valve seat 47 at the outer end on which is seated-a valve 48. There is preferably a clearance space 49 in each of the cylinder heads 20. The valves are providedwvith valve stems 50 slidable through theplugs, and have washers 51 secured at the ends with compression springs 52 acting between the washers and the plugs, thus normally holding the valves seated.

The common yoke 39'is provided with studs refrigerating machines and is adapted to" compress carbon dioxide, sulphur dioxide or ammonia gases,the-se asesbeing compressed and condensed in the tank 27'. The intalre gases from the refrlgerating mach ne are drawn intothechamber 16 through the inlet opening 42 and when a piston is being drawn out of its cylinder into the chamber 16,

1 the gases pass through the ports 43, and :due

V of Fig. 2, that the cam is constructed in to-the fact that the gases have a pressure sufficient to compress the springs 52 seating the valvesi48', the gases are forced tnroughsiich valves, the valves raising slightly from their seats. The partial vacuum caused by the drawing of the piston from its cylinder causes the spaces between the piston and the cylinder head to be filled with the gases, for, on account of the check valve 23, none of the gases can be withdrawn from the tank 27. On the compression stroke, that is, when each piston is being'forced into its cylinder, the valve 38 is seated and thus forces thegas'through the pas-sage 21 andlthe outlet 22 opening the check valve 23; The gas then flows through the pipes 26 into the receivingtank 2'7.

s It willbe noted, especially by observation such a manner that those portions of the cam 7 face intercepted by-the planeincluding the axis of rotation of the shaft 28 and the center of the cam 55, are of greater radius of curvature than the mean radius of curvature of the remaining portions of the cam surface, i. 6., these specified portions of the cam surface are-more nearly fiat than the other por- 'tions,; w,ith the result that when the rollers 54 are traversing these specified portions of they cam surface,the motion of the connecting rod;39r and its pistons .88, isv at its lowest velocity. Since these portions of greatest type ofaotion,thus'adding materially to the, 7 e5 radius of curvature are in the line of ec'cenf I tricity' of the cam, theperiods of minimum acceleration of the rod andfpistons, occur while the pistons are at-the'ends of their stroke, with the result that the acceleration of the pistons at the end of their stroke is con siderably less than with a crank typeofaction. Iii other words,the pistons are'brought to rest more gradually and start their return motion more gradually than 'ith the crank avoidance of vibration, andhence,decreasing noise caused by the operative parts ofthe compressor. I

It is to be further noted that although the cam has been flattened as above described,

' upon two opposite sides, the diameter of the cam when measured through the axis of rotation of the shaft 28, is constantthrouglr out the entire periphery of the cam and substantially equal to the distance between the proximal faces of the rollers 54;, with the result that play between thecam and yoke is minimized. i I

1 Various changes may be made in the principles of my invention Without departing from the spirit thereof, as set forth in the lclaiinn .7, "l. A compressor coniprlsingin .co nbina description, drawings and claims .j'

'tion a frame havinga back Wallpforvvardly extending walls therefroniiand a removable cover plate forming a:chambenlashaftjoun naled in" the back .walliand the cover plate and having a'cam thereon in the chamber, a

7 pair of cylinders secured to the oppositesides of the forwardly ext'ending'walls, heads se cured to said cylinders, pistons slidable in the cylinders being connected by a cominonyoke, interengaging means 'betweenthe ,yokeand the said cam, an inlet to the chamberythe pistons having ports connecting to thecha nber,

check valves in the pistons, a removable tank secured in the said frame, and discharge out lets-from thecylinder heads to the said tank, said discharge having check valves tion a casing, :a shaft journaned therein, a cam carried by said shaft, those [portions of the face of the camQinterce pted by the plane including the centers ,of the shaft and calm being ofggreater radius of curvature than the mean radius of curvature of the remain-, der of the cam surface, axially aligned cyline I reciprocable ithin said cylinders, common yoke rigidwith saidp'isto'ns and havinga ders at opposite sides,ofsa dcasing, pistons aio horizontal slot forthe reception.ofsaidshaft V and averticalslot'ifor; the reception or said cam, a stud extending across; said vertical'slot adjacent each endthereof,a roller revolubly mounted uponeach studand inlengagement with said cam, means forladhii ttingfluid to said", ylinders, and m'eans; .forf'conductingfluid away 'froin' s'aid" cylinders. Ii i 3. In I a pump a pair of axially; aligned cylinders, "a shaft; ournalled f fojr rotation be,- tween' the-cylinders and perpeiidicularito the common axis thereof,,a piston reciprocable in each cylinder, a common yoke rigid. with both pistons,a cam rigidlyandeccentrically mounted upon said shaft, a pairrof rollers revolubly V mounted upon .said .yokerz in p il 1 7 tion to simultaneously; engage opposite sides of 's'aidcam, those portions ofthe face of the C .i er r edby th vPla e ne nd nsat enters the s a tan' mm'be ng Of gr a r radius of curvature than the mean radius of gurvature of the remainder of the cam surace.

4. In a pump, a pair of axially aligned cylinders, a shaft journalled for rotation between the cylinders and perpendicular to the common axis thereof, a piston reciprocable in each cylinder, a common yoke rigid with both pistons, a cam rigidly and eccentrically mounted upon said shaft, a pair of rollers revolubly mounted upon said yoke in position to simultaneously engage opposite sides of said cam, those portions of the face of the cam intercepted by the plane including the centers'of the shaft and cam being of greater radius of curvature than the mean radius of curvature of the remainder of the cam surface, and the diameter of the cam measured through the center of the shaft being constant throughout the entire periphery ofthe cam. I

Intestimony whereof I have signed my name to this specification.

SAMUEL W. LUITWIELER. 

